SUMMARY In the Proteomics Core (Core C), part of the Dengue Human Immunology Project Consortium, we will apply mass spectrometry-based proteomics approaches to quantitatively measure responses to viral infection and vaccination in clinical cohorts. We will first measure global changes in a number of protein readouts including phosphorylation, ubiquitination, and protein abundance, in ex vivo primary cells infected with Dengue virus to identify proteins of interest worth pursuing in more targeted proteomics studies in clinical samples. Data from Core C will be integrated with data from Cores B (Genomics Core) and D (Immune Monitoring Core) by Core E (Data Analysis and Modeling Core) to select approximately 200 proteins for which to develop sensitive assays for detection and quantification from very limited sample amounts. Finally, we will apply the developed assays to quantify protein responses in patient-derived samples from clinical cohorts in natural populations to compare clinical outcomes of viral infection and vaccination. These targeted proteomics approach will also be used to conduct ex vivo validation studies after perturbing predicted host driver genes.